Question: When was Boleslaw Bierut came to the position of President of Poland?
Paraphrase: When did Boleslaw Bierut become Poland's President?
SPARQL (Wikidata): SELECT ?value WHERE { wd:Q55832 p:P39 ?s . ?s ps:P39 wd:Q1054799 . ?s pq:P580 ?value}